Telegraph system



9 M. T. GOETZ TELEGRAPH SYSTEM Filed July 14, 1945 3 Sheets-Sheet 1 MULTIPLEX RELAY TRfirfiilhgzgiR MULIFEEX RECETIVPINCX T0 BANK M CHANNEL MUL LE START-STOP DISTRlBUToR DISTRIBUTOR I CONVERTOR ,r l 206 zos FTAPE 1 TAPE V TRANSMITTER' INPUT TRANSMiTTER' I E 1- IREPERFORATORI DISTRIBUTOR 'DISTREBUTOR v CIRCUIT j T0 29 (OUTPUT) TO START- STOP 263 START- STOP CIRCUIT MONITOR cmcurr FlG.l 'RELAY BANK ATTORNEY M. T. GoErz TELEGRAPH SYSTEB l Sept. 20, 1949.

3 Sheets-Sheet 2 Filed July 14, 1945 In l- PM In .F 9 L Z T u m G Y T M H W S N U T l M U A M 7 M wk Patented Sept. 20, 1949 UNITED STATES PATENT OFFICE type Corporation, Chicago, Ill., a corporation Delaware Application July 14, 1945, Serial No. 605,082 V 12 Claims.

The present invention pertains to telegraph systems, and more particularly to systems incorporating both multiplex and start-stop transmission and apparatus.

On multiplex channels the use of a blank combination indicates an idle condition, and therefore means are usually provided at the receiving end to suppress blanks. In the event that start-stop channels and apparatus are connected to such multiplex channels and messages are transmitted containing needed blank combinations, it becomes necessary to provide means to distinguish the blank combination from an idle channel condition.

Accordingly, an object of the present invention is to provide means for determining the difference between a blank combination and an idle channel condition.

A further object of the invention is to convert a blank combination to a different character combination and a letters combination for multiplex transmission and to reconvert the combinations to a blank combination.

Inasmuch as there are a limited number of code combinations available in the five unit Baudot code, in the event that a blank combination is converted to a diiferent character combination the latter will thus be useless for intelligence communication, which under certain conditions is undesirable.

Accordingly, a further object of the invention is to provide means whereby no code combinations will be sacrificed, to achieve the objects set forth previously.

Still another object of the invention is to provide means to convert the character combination used to designate the blank combination to a double character combination, and thereafter to reconvert to a single combination.

Another object of the invention is to convert predetermined code combinations only to different code combinations, and to reconvert them to the original code combinations.

A still further object of the invention is to provide means to distinguish between various code signals.

An embodiment of the invention, utilized with reperforator transmitters, comprises, at the startstop to multiplex changeover, a plurality of reading contacts and relays operating to convert a blank combination to a different character combination and a letters" combination and to convert the different character combination to a double character combination. Likewise, means are provided including reading contacts and re- 2 lays to reconvert to the original characters at the multiplex to start-stop routing point.

The features and advantages of the invention will become apparent from the following detailed description of a specific embodiment thereof, when read in conjunction with the accompanying drawings, in which Fig. 1 shows a block diagram of the contemplated system; V

Fig. 2 shows the means to convert the code combinations at the point of start-stop to multiplex change;

Fig. 3 shows the means to reconvert to the original code combinations at the routing point from multiplex to start-stop transmission, and

Fig. 4 illustrates a partial view of apparatus with which the'present invention may be readily utilized.

The specific embodiment of the invention has been shown in conjunction with a start-stop reperforator transmitter of the type disclosed in U. S. Patent No. 2,348,214, issued to E. A. Gubisch on May 9, 1944. Fig. 4 of the instant drawings is a portion of Fig. 2 of'the Gubisch patent, with the identifying numerals changed to apply to the following description. It is to be understood, however, that the invention is not limited to incorporation with such apparatus but may be utilized with signal transmitting and receiving apparatus of any suitable type.

Referring particularly to Fig. 1, apparatus is disclosed for converting signals in the startstop to multiplex routing. The apparatus at such station contemplates the use of a start-stop perforator transmitter H which is of the type disclosed in the above-identified patent. A relay bank i2 is provided in conjunction with the transmitter I! and a multiplex distributor i3 is provided in conjunction with the relay bank E2.

The perforator transmitter H operates from a tape which is shown in Fig. 1 of the instant drawings and which is sensed by means of a plurality of feeler levers (not shown) in a manner well known in the art. As a result of the sensing operation of such feeler levers, a plurality of slides l4 (Fig. 2) are ultimately set in accordance with the marking or spacing characteristic of the particular code combination. The slides l4 operate through a projection i6 forming part of each of a plurality of contact operators I! which are pivoted on a shaft i8, all as is clearly described in the above-identified patent, and as is shown in Fig. 4. It is not deemed necessary to describe the operation of the elements of Fig. 4 as a complete description may be found in the 3 Gubisch patent. The contact operators l1 have an elongated section H! which has a plurality of lugs 2i thereon, each of which engages an associated swinger to control the operation thereof in a manner which will be described hereinafter.

A shaft 22 is" provided which controls the operation of the setting ofthc swingers described above and which also has cams 23 and 24 thereon for causing operations which also will be described hereinafter. The shaft 22 is under the control of a clutch magnet 26 to release said shaft for operation as will be described. A secon-d shaft 21 is provided which has a pmaliity ofi cams 28; thereon which control the transmission of startstop code signals over a start-stop circuit 29. Such start-stop transmission may be utilized to control a monitor printer at the localstation, which is not shown iri the present invention, or may be utilized for start-stop'transmission to any other locality, The shaft 21 is under the control of a clutch magnet 3t, as will hereinafter be described.

If it is assumed that the transmitter H- is operating with the slides M being positionedin accordance with the permutations in the tape, the contact operators I! will likewise be positioned in accordance with the operation of the slides through the projections l6 and because of the lu 2| extending from the elongated portion [9 will cause the operation of a first set of electrical contacts 32 in accordance with the setting of the slides l4.

By reference to the cams 28 onthe shaft 21, it

may be seen that each of these controlsan associated cam follower 33- which is pivoted at 34 and,

has a downwardly extending contact operating arm 33. The cam followers 33 are each normally biased in a clockwi-se 'direction into engagement with the periphery of their associated cam by means of an individual spring 31. Upon rotation 33 associated therewith with the resultant removal of a marking condition from the circuit 29. After this contact pair is opened a zero or start condition will exist for a predetermined time. Immediately thereafter the remaining five contact pairs 38 will be closed sequentially in a manner which has previously been described. Upon the closure of the contact pairs 38 code impulses will be transmitted over the conductor in accordance with the sensing of the perforations in the tape in a manner which will now be described.

If it is assumed that the particular code combination that has been sensed in the tape comprises a marking and spacing condition, respectively, for the first two impulses, the uppermost contact pair 32 will be closed whereas the second contact pair 32 (immediately therebelow). will be open. 7

With respect to the 'topcontact pair 32, at the time that the uppermost contact pair 38' is closed an electrical circuit will be established from grounded positive battery 48, over a common conductor 33, through the uppermost contact pair stop circuit 23.

be transmitted over thecircuit underthis condicui-t similar to the one just described because' 32, over a conductor 5i, through the closed ,uppermost contact pair 38, over a conductor 52, and over the common conductor 53' to the start- Thus, a marking impulse will tion. 7

Considering now the second contact pair 32 which we have assumed to be in an open condition due to the sensing of a spacing condition y (no perforation) in the tape with respect to the second contact pair 38 atsuch time as that conestablished from the battery, through a cirof the fact that as mentioned the contact pair 32 associated therewith is open. Such being the case a zero-electrical or spacing condition will of the shaft 21, because: of the staggered recesses V in the cam with respect to each of the follower levers 33, the follower-levers will be operated sequentially in a clockwise direction to cause the downward extension 36 thereof to close an asso-' ciated contact pair 38.

By reference to the drawing it may be seen that the lowermost camv follower 33 is normally biased in a clockwise direction to close its associated contact pair 38 because of. the fact that when the shaft 21 is at rest, the recess of the cam 28 associated with the lowermost cam follower 33 is presented to the cam follower thereby allowing the contact pair 33 to be closed. Under this condition an electrical circuit is established from positive grounded battery 39, through the normally closed contact pair 38, over a conductor 4|, and over the start-stop circuit 29. This con dition is the normal idle condition on the startstop circuit with marking battery on the line.

If it is further assumed that the shaft 22 is operating, at a particular time in its cycle of rotation the cam 23 thereon wilt allow an associated follower lever 42 to be biased in aclockwise direction under the urging of its spring 43 to close an associated contact pair 44. At this time an electrical circuit will be established from positive grounded battery 46', through the closed contact pair 44, over a conductor 41, and through the winding of a clutch release magnet 3! to ground. Such operation will cause the shaft 21 to be released for rotation thereby opening the lowermost contact pair 38through the resulting occur on the circuit. ZQY-during thisinterval.

Thereafter, the remaining three contact pairs 38 will be closed at successive intervals and Will cause marking or spacing impulses to be transmitted over the circuit 29in accordance with the settings of their associated contact pairs 32 under the control of the tape in a manner which has just been described. 7

After the shaft 21 has completed a cycle of operation it will come to a stop condition and will remain in such condition until such time as the clutch release magnet 3| is once again energized to'relea'se it for another cycle of operation. Such will occur after the shaft 22 once again assumes a position whereat the depression in the cam 23 is presented to the follower lever 42 thereby once again closing the contact pair 44 and establishing the circuit described previously.

The start-stop circuit 29 will be under the control of the'apparatus described above to transmit code signals to its associatedreceiving equipment.

Inasmuch as this does not form part of' the present invention, however, further description thereof is not deemed necessary with the exception that the time of closure of the contact pair with respect to the entire apparatus will be pointed out hereinafter.

The elongated section IQ of a contact operating lever 11 not only controls, a contact pair 32 through its lug 21, but through a similar lug controls a movable swinger 54 which in a normal or unoperated position will be in engagement with a right-hand contact 55 and in an operated or selected condition will be in engagement with a left-hand contact 51. The elongated portion 19 through another lug 2! also controls a movable swinger 58 which in its normal unoperated condition is in engagement with a right-hand contact 59 and in a selected condition is in engagement with a left-hand contact 5!. Likewise, another lug 2| also controls a movable swinger 62 which is normally in engagement with right-hand contact 63 but when moved to a selected position engages a left-hand contact 54. While the above description has been given with respect to a particular elongated portion I9 of contact operating lever l1 and the swingers which it controls. it is to be understood that each of the five contact operating levers l1, each designating one of the impulses of the five unit code, will control in a similar manner similar swingers 55, 58, and 62.

If it is assumed that the transmitter l l is in an unoperated condition with all of the slides [4 in an unselected position, which indicates that their associated feeler has not sensed a perforation in the tape or that no tape is present in the apparatus, the elongated section 19 will be in its extreme right-hand position thereby resulting in the swingers 54, 58, and 52 being in engagement with their right-hand contacts 56, 59, and 63, respectively. Under this condition an electrical circuit may be traced from positive spacing grounded battery 66, over common conductor 61, through the contacts 63, through the swingers 62, and over individual conductors 68 to the relay bank l2 for a purpose to be described hereinafter. It might be mentioned at this point that this condition of positive battery or "blank on the line indicates an idle condition under multiplex transmission, such condition being spacing on the line.

As has been previously mentioned, the swingers 54 and 58 are also in their unselected or righthand position in engagement with their associated contacts 56 and 59, respectively. It is sufficient to state at this time that no electrical circuit will be established due to such positioning of the swingers 54 and 58 because in an unoperated condition of the transmitter H and particularly the shaft 22, the cam 24 thereon will not permit its associated spring to bias its associated follower 69 in a clockwise direction to allow the closure of associated contact pair 19 thus precluding the establishment of an electrical circuit from the grounded battery 46, through the contact pair H1. The significance of this contact pair l9 and the operation as a result of its closure will be described fully hereinafter.

If reference is now made to the multiplex distributor 13 it may be seen that it comprises a ring H having a plurality of segments thereon, the first five of which are connected over conductors 12 to the relay bank l2. The segmented ring H is contemplated to include twenty segments, thereby providing for transmission over four channels, one of which is disclosed in the instant drawings. The segmented ring H is bridged by means of an associated brush in a manner well known in the art with a solid transmitting ring 13 to initiate multiplex code signals over a line conductor 14. The multiplex distributor I3 is further provided with a local solid ring 16 which is connected to positive grounded battery 11. Solid ring 16 is bridged by an associated brush with a local ring 18 which is provided with local segments thereon, one of which, 19, is shown. A segment 19 is associated with each of the multiplex channels.

' If it is assumed that the present apparatus has not been operating and that the distributor brush has traversed the segment 19 of the local ring 18, an electrical circuit will be established from grounded battery 11, through the solid ring 16, over the brush in a well known manner, through the segment 19, over a conductor 8|, through an armature 82 to lower contact 83 with which it is normally in engagement, over a conductor 84, through an armature 86 to lower contact 81 with which it is normally in engagement, over a conductor 88 to junction point 89, over conductor 9|, through the Winding of clutch release magnet 26, through a manually operable switch 92 which will now be closed, over a conductor 93 and through a swinger 94, through contact 96 normally in engagement therewith, to ground. Upon the establishment of the circuit just traced, the clutch release magnet 26 will be energized, thereby resulting in the release of the shaft 22 for rotation.

The swinger 95, which has been described as normally being in engagement with contact 96, is under the control of a member 9'! which, as is described in the above-identified patent and is also illustrated in Fig. 4, operates when the pivoted sensing device is in engagement with the punch block thereby indicating that the last code combination in the tape has been sensed and that no more tape is available for transmission. Under such condition the member 91 would cause swinger 94 to be biased in a counterclockwise direction removing it from engagement with contact 96 and thereby precluding the energization of the clutch release magnet 26, even though the distributor brush traverses the segment 19.

The switch 92 previously mentioned is provided so that if it is desired to preclude operation of the instant apparatus the switch will be opened thereby preventing the establishment of the circuit for magnet 26. Under this condition the clutch release magnet 29 will not be energized, assuming that the switch 92 has been placed in an open position, even though the brush traverses the segment 19.

During the first part of the cycle of rotation of the shaft 22 the feeler levers will be removed from the tape thereby allowing the tape to be stepped and thereafter will be once again placed in probing engagement with the tape to thereby set the slides l4 and the contact operators IT in accordance with the impulse characteristics or conditions in the tape.

Just prior to the setting of the contacts in accordance with the code combinations in the tape, the cam 23 on the shaft 22 will operate to close the contact pair 4% and thereby cause the energization of the clutch release magnet 3!, as has been described. Such results in marking battery 39 being removed from the line conductor 29 and a zero condition or start pulse being transmitted on the line. During the transmission of the start pulse the contacts under the control of the contact operators I! will be set and thereafter the contacts 38 will be closed sequentially to transmit marking or spacing impulses over the line conductor 29.

Inasmuch as swingers 62 will now be positioned in accordance with the code combinations in the tape they will not all remain in their right-hand position in engagement with associated contact 63 unless the particular combination sensed happens to be an all-spacing or blank combination. Assuming that such is not the case and that certain of the swingers 62 have been moved to their left-hand position in engagement with associated contact 66, an electrical circuit will be established from negative grounded marking battery 98, over common conductor $9, through contacts 64, through swingers 62' which have been moved to the left and over conductors 68110 the relay bank I2. Unless the particular code combination is an all marking or letters combination certain of the swingers 62 will remain intheir unselected or right-hand position in engagement with associated contact 63. Under this condition the previously described electrical circuit from positive spacing battery 68 to conductors 66 will be established. Under the conditions described above, the code combinations sensed of marking and spacing impulses will be passed over the conductors 88 to the relay bank I2. The above operations will be repeated for each character to transmit message intelligence over the multiplex circuit through the relay bank I2 and over the segmented and solid rings H and 13, respectively, in a manner which will be described hereinafter. The transmitter H will be reset to a new code combination every time that the brush traverses the segment 19 of the local ring 18 to re-energize the selector magnet 26. It should be noted, as previously mentioned, that the instant apparatus utilizes one channel only of the multiplex circuit and, therefore, the tape will be stepped and the contacts set while the brush is traversing segments similar to the first five segments of segmented ring TI associated with other multiplex channels. Thus, the instant apparatus will be in readiness to transmit a code signal at such time as the brush traverses the first five segments of the segmented ring 1I.

If it is assumed that a blank code combination is sensed in the tape, the selector operators I1 will all remain in their extreme clockwise position resulting in the elongated portion I9, through the lugs 2|, not exerting any pressure on any of the swingers 54, 58, or 62. As a result of such condition all of these swingers will remain in their unselected or right-hand positions in engagement with the contacts 56, 59, and 63, respectively. It is to be remembered that'previously a blank combination was indicated as an idle channel designation for the multiplex apparatus and stated as occurring during the time that the transmitter II was not operating. However, because of the fact that the blank combination now occurs during the transmission of a message it is undesirable to allow such combination to be transmitted over the multiplex channel thereby indicating to the receiving equipment that an idle condition exists.

In order to remedy such condition it should be noted that the contact 56 associated with the uppermost or first swinger 54 is connected by means of a conductor IOI to the contact 56 associated with the second swinger, immediately thereunder. This swinger is connected by means of a conductor I02 to the third or middle swinger 54; this contact 56 is connected over conductor I03 to the fourth contact 56. The fourth swinger 54 associated with this contact is connected over conductor I04 to the contact 55 of the fifth or lowermost swinger 54 which is connected by means of conductor Ifit to junction point I01 At such time as the cam 24 on the shaft 22 presents its depression to the follower lever 65%, which occurs after the feeler levers are moved to their upward tape sensing positions and which is before the contact pairs are set, the follower lever 69 will be pivoted in a clockwisedirection under the urging of its spring to momentarily close the contact pair 10. When such occurs, an electrical circuit is established which may be traced from positive battery 46, over a conductor I08, through the closed contact pair 10to' junction point I01, over the conductor I06, and through the circuit previously traced of the swingers 54 in their unselected positions and the conductors I04, I03, I02, and IIJI, through the up.- permost swinger 54, over. conductor I06, and through the winding of a relay IIIto ground. Upon the energization of the relay- I II its armature H2 will be attracted thereto which results in the establishing of a locking circuit for the relay which maybe traced from ground through the winding of relay III, through the armature I I2 and the contact associated therewith with which it is then in engagement, over a conductor II3 to junction point II4,-over' a conductor H6 to junction point 1, over a conductor IIB'to a contact vHi3, through the armature I2I which is normallyfinengagement with the contact H9, and over a conductor I22 to positive grounded battery I23. Thus, the relay III will remain in its energized condition until such time as the armature I2I is removed from engagement with the contact II 9-,. as will be described hereinafter. Upon the energization of the relay III its armatures I24 to I28, inclusive, will also be attracted thereto. As may be seen, the upper contacts associated with the armatures I24 to I28, inclusive, are connected by the conductors 68 to the swingers 62 at the transmitter II. The lower contact associated with the armatures I24 and I26 to I28, inclusive, are connected by means of a common conductor I 3I to negative grounded marking battery I32. .The lower contact associated with the armature I25 is connected o-ver conductor I33 to an armature I34 which may move between an upper contact which is connected by conductor I36 to positive grounded spacing battery I31 and a lower contact connected over conductor I38 to a negative grounded marking battery I30. .How-

ever, at this time the armature I34 will be in engagement with its upper contact.

At the same time as the above circuit was established upon the-momentary closure of the contact pair 10, a second circuit is established which may be traced from grounded battery 46, over the conductor I08, through the closed contact pair 10 to junction point I01, over a conductor I iI and grounded battery I23. The re1ayl42 will remain in an energized condition until locking battery is broken by the removing'of armature I2I from contact H9, as will be hereinafter described. As a result of the energization of relay I42 its five associated armatures I48 will also be attracted thereto to remove them from engagement with their upper contactswhich previously were connected over common conductor I49 to positive grounded spacing battery I5I andinstead place them in engagement with associated lower contactslwhich are connected over conductors I52 to five armatures I53 to I51, inclusive. 'The armatures I53 to I51,- inclusive, are movable between upper contacts which are connected by means of conductors I59 to the armatures I24 to I28, inclusive, respectively, previously described. The lower contact associated with the armatures I53 and I 55 to I51, inclusive, are connected over a common conductor I6I to negative grounded marking battery I62 whereas the lower contact associated with the armature I54 is connected to positive grounded spacing battery I63.

It should be noted that at the time relay III becomes energized its armature 86 will also be attracted thereto thus breaking the circuit which had previously been traced through the armature 86 and the lower contact 81 from the local segment 19 for the energization of the clutch magnet 26.

Remembering now that the relays III and I42 both are energized and held in that position, thereby attracting the armatures I24 to I28, inclusive, and the armatures I48 thereto, respectively, a line circuit is established which may be traced from negative marking battery I32 over the common conductor I3 I, through the armature I24 which is in engagement with its lower contact, over the conductor I59, through the armature I53 which is in engagment with its upper contact, over the conductor I52, through the first or upper armature I48 which is in engagement with its lower contact, to the No. 1 segment of the segmented distributor ring 1I. At such time as the brush traverses the No. 1 segment, the circuit will be further traced through the brush, over the solid ring 13, and thence over the line conductor 14 to the multiplex channel. Such will result in the No. 1 impulse of the code combination being transmitted over the multiplex circuit as a marking condition.

It is to be remembered that the armature I25 was previously described as not being connected to common conductor I3I but instead as being connected over conductor I33. Thus, the next circuit which may be traced will be from positive spacing battery I31, over conductor I35, through the armature I34 now in engagement with its upper contact, over the conductor I33, through the armature I25 in engagement with its lower contact, over the conductor I59 to the armature I54, thence over the conductor I52 and through the second armature I48 now in its lower position, and over the conductor 12 to the No. 2 segment of the segmented distributor ring 1 I. At such time as the brush traverses the No. 2 segment a positive spacing impulse will be transmitted from the No. 2 segment over the brush, through the solid ring 13 and over the line conductor 14 to the multiplex channel, as the No. 2 impulse of the code combination.

If the circuits were to be traced which are established by the attraction of the armatures I26, I21, and I28 in engagement with their lower contacts, it would be seen that they would be traced similarly to that traced with respect to the armature I24. Therefore, as the brush traverses the Nos. 3, 4, and segments, negative marking impulses will be transmitted over the line conductor 14 as the remaining three impulses of the code combination.

As a result of the circuits traced immediately above, we have seen that the code combination transmitted will consist of a negative marking impulse, a positive spacing impulse, and three negative marking impulses. Thus, instead of the transmission of a blank code combination, designated by five spacing impulses, which had been sensed in the tape, an entirely different code combination has been transmitted over the multiplex channel which in the particular illustration consists of the code combination for the character X.

After the brush has traversed the first five segments of the segmented ring H at some later time the brush associated with the local rings 16 and 18 will traverse the segment 19 associated with the particular apparatus which would normally cause the energization of the clutch magnet 26, resulting in the tape being stepped and a second combination being presented to the feeler levers. However, this will not occur because, as described above, the armature 86 was attracted upon the energization of the relay I I I thereby breaking the previously established circuit for the energization of the clutch magnet 26. Instead, an electrical circuit will be established which may be traced from the battery 11, through the solid ring 16 and the brush associated therewith, through the segment 19, over the conductor BI, through the armature 82 and the associated lower contact 93, over the conductor 84, through the armature 86, through the upper contact associated therewith, over the conductor I64 to junction point I66, through the armature I61 normally in engagement with its lower contact, over the conductor I68, and through the winding of a relay I69 to ground. As a result of the energization of the relay I69 a locking circuit is established from ground, through the winding of the relay I69, through the associated armature I1I attracted thereto, over the conductor I12, through the winding of relay I13 to junction point I I4, thence over conductors H6 and H8, through contact H9 and armature I2I, and over conductor I22 to grounded battery I23. The relay I13 which has been energized as a result of the locking circuit for the relay I69 causes its armatures I34 and I61 to be attracted thereto. As a result of the attraction of the armature I34 it will be moved from engagement with its upper to its lower contact thereby precluding positive spacing battery I31 from being connected with the armature I25 but instead connecting this armature with negative marking battery I39 by means of the conductor I38, the armature I34, and the conductor I33 to the armature I25. It might be noted that the relay I13 does not become energized until some time after the brush has completely traversed the segment 19.

As a result of negative marking battery I39 being impressed on the armature I25, at such time as the brush associated with the segmented ring 1I passes over the other three channel segments previously mentioned but not shown, and returns to traverse the first five segments connected over the conductors 12 to the relay bank I2, marking battery will be applied to the No. 2 segment. Inasmuch as the relays III and I42 are still in an energized condition through their looking circuits, as is relay I13, at the time that the brush traverses the No. 1 segment, an electrical circuit is established as previously described from negative marking battery I32, over the common conductor I3I, through the armature I24, over the conductor I'59 to the armature I53, over the conductor I52 to the uppermost armature I43, over associated conductor 12 to the No. 1 segment of the segmented distributor ring 1I, thence through the associated brush, through the solid ring 13 and over the line conductor 14 to the multiplex channel. Under this condition a marking impulse designating the No. l impulse of the code combination will be transmitted over the line. It

to rememberedthat under the prior descrip- 7 tion it was described that a spacing impulse was sent as the brush traversed the No. 2 segment. However, due to the .energization of the relay I13 as the brush traverses the N0. ,2 segment'an electrical circuit will be established from negative marking battery I39, over the conductor I38, through the armature I34 which is in engagement with its lower contact, over the conductor I36, through the armature I25 which is in engagement withits lower contact, over the conductor I59, through the armature [54, over the conductor I52 and through the second armature I48, through the conductor 12 to the No. 2 segment, through the brush to the soliddistributor ring I3, and thence over the line conductor I4 to the multiplex channel. Thus, a marking impulse will now be transmitted as the. ,No. Zimpulse of the code combination. l 7

As the brush sequentially traverses the third,

' fourth and fifth segments of the segmented ring .lI electrical circuits will be established from the negative marking battery I32 to the armatures I25 to I28, inclusive, and over circuits similar; to that described with respect to the armature I24 to the Nos. 3, 4, and segments of the ring H. As a result of such condition itgmay be seen that the entire code combination-transmitted over the line conductor 14 t0 themultiplex channel will consist of negative marking impulses which under the standard code designates a letters combination, It is to be remembered that during the time that the X and letters combinations were transmitted. as a result of the sensing f a blank code combination in, the tape. e ap has not been stepped to its next code combination but has been held in. the. same position.

Inasmuch as the clutch release magnet 2% was not energized duringv the transmission of the 1et ters combination the shaft 22 is not released for a cycle of rotation and,.therefore,,no electrical circuit is established-fertile energiz 0 t clutch release magnet 3|, associated, with the shaft 21. Therefore, durin this periodoi time no code combination indicative of a letters combination will; be transmitted over the startstop circuit 29." a

Sometime afterth-e code combination of. letters has been transmitted over the linegconductor E4 to the multiplex channel, the distributor brushes will be advanced to a position whereat one of them will traverse the segment 79 of the local ring 18. At thistime an electrical circuit will be established. which may be traced from grounded battery I1, through the solidring 76' and the associated. brush to the segment it, over the conductor 8|, through the armaturefiz gization, As a, result of such occurrence the armatures which hadbeen attracted by the energization of the various relays will return to their original position and the apparatus will now be in a normal condition ready for the transmission of another character.

Simultaneously with the energization of the relay I'I'I over the circuit described above, a second electrical circuit is established which may be tracedover the circuit just traced above to' junction point I16, and thence over conductor I18 to junction point 89, over the conductor 9!, through the winding of clutch release magnet 26, through the manual switch 92, over the conductor 93, through the swinger 94', through the associated contact 96 and to ground. As a result of the energization of clutch magnet 26 the shaft 22 will be released for rotation which, during the early part of its rotation, will cause the tape to be stepped and the contact operators I7 to be set in marking or spacing position in accordance with the code combination in the tape sensed by the feelers (not shown). Thus, the apparatus is once again ready to trans.- Init a code combination at such time as the brush traverses the first five segments of the segmented ring II associated withthis channel.

to the associated lower contact 83, over the conductor 84, through the armature Stand its upper contact with which it is now in engagement, over the conductor I64 to junction point I6 6 through the armature I61 which is now in engagement with its upper con-tactdue to the looking battery applied-to relay I13, over conductor I14 to junction point H6, and through the winding of a relay I1 7 to ground. As a result of the energization of the relay II'I its armature 'I2I will be attracted thereto, thereby removing it from engagement with, its associated contact H9. Inasmuch as the locking circuits for the relays I42, I I I, I13, and I69 had all been traced through the contact -.I I9. and the armature I2! to battery I23, such circuits will now be broken As was previously mentioned, the present apparatus provides means so that in the event that the character used to designate a blank con dition in a message text on the multiplex channel is sensed in the same or another message text, a different designation will be transmitted over the multiplex channel so that the two may be distinguished from'each other at the receiving station. Inasmuch as the character utilized to indicate a blank code combination was picked as the character X an assumption will now bemade that the tape. transmitter has'sensed an X code designation which consists ofa' marking, spacing, and three marking impulses. As a result of such sensing the elongated members I9 will cause. thefirst, thirdfffourth, and fifth swingers 58 to be positioned to their selected or left-hand positions in engagement'with their associated, contacts BI, whereas the second swinger. 58 will remain in its unselected or righthand. position inengagement with its associated contact 59. At such'time as'the shaft 22 advances sufficiently to cause. the cam 24 to operate the follower 68 and thereby close the contact pair 'Iflmomentarily, an electrical circuit will be established which. may be traced from grounded battery-46, over theconductor- I I18 and through the contact pair 10 to junction point I 01, over the conductor I4II and through the winding of .relay I42 to ground; Relay. I42 willimmediately become energized and will then .be locked up through the armature. Hi3 associated. therewith to the. battery I23 in a, ma n similar t that described previously for relay, I42. As a result of such .energizationof relay I42 the armatures I 48. will be attracted thereto and positioned in 7 a ement; with their lower contacts. A sec- .ondcircuitwlll alsohe. established which may 7 be traced from grounded battery 45, over conand locking battery will be removed from all of-v these relays thereby resulting in their de-ener rductor I08. and through gthe co ntact pair I0 to 5a, through the left-hand contact as which it engages, over the conductor I84 to the second swinger 58, through the right-hand contact 59 with which it is in engagement (No, 2 swinger not selected due to spacing condition), over a conductor I86 and through the first swinger 58, through the left-hand contact 6| with which it is in engagement, over conductor I81, and through the winding of relay I88 to ground. As a result of the energization of the relay I88 its associated armature I89 will be attracted thereto which will result in looking battery being applied to this relay from ground, through the winding thereof, through the armature I89, over a conductor I9I to junction point I 46, over the conductor I41 to junction point I I1, and thence over the conductor II8, through the contact I I9, through the armature I2I, and over the conductor I22 to grounded battery I23. The relay I88 will thus remain in an energized condition until such time as its locking circuit will be broken which will be described hereinafter.

Also as a result of the energization of the relay I88 its armatures I53 to I51, inclusive, will beattracted thereto placing them in engagement with their associated lower contacts. As a result of such movement of the armatures an electrical circuit may be traced from negative marking battery I82, over the common conductor IBI to the lower contact with which the armature I53 is in engagement, through the armature I53, over the conductor I52, through the first armature I48 which moved to its lower contact upon the energization of the relay I42, and over the conductor E2 to the No. 1 segment of the segmented distributor ring 1I. Thus, at such time as the associated brush traverses the No. 1 segment a marking impulse will be transmitted over the line conductor 14 to the multiplex channel.

The second armature I54 was also moved to its lower position but instead of deriving battery over the circuit just described it will instead derive it from positive spacing battery I83 and the lower contact associated with the armature I54. This circuit may be further traced through the conductor I52, the second armature I48, and the conductor 12 to the No. 2 segment. Thus, as the brush traverses the No. 2 segment a spacing condition will be applied on the line conductor 14.

The armatures I55, I56, and I51 are connected to negative marking battery I82 in a manner similar to that as described with respect to armature I53 and thus, as the brush traverses the Nos. 3, 4, and segments of the segmented ring II marking impulses will be applied to the line conductor 14. Thus, a code combination will be transmitted over the multiplex channel indicative of the character X.

Inasmuch as the shaft 22 was released for rotation, as previously described, at an appropriate position in its cycle the cam 23 will cause the contact pair 44 to be closed thereby resulting in the energization of the clutch release magnet 8! which allows the shaft 21 to rotate and thereby transmit an X character designation over the start-stop circuit 29 in a manner which has previously been described,

After the transmittal of the X code combination over the multiplex channel as a result of the brushes traversing the first five segments of the segmented distributor ring 1|, the brush associated with the solid ring 16 and the local ring 18 will at some later time traverse the local segment 19, thereby resulting in an electrical circuit being established from grounded battery 11, over the solid ring 16 and the bridging brushes,

through the segment 19 of the ring 18, over the conductor 8|, through the armature 82 to its upper contact with which it is now in engagement, over a conductor I92 to junction point I86, through the armature I81, through the lower contact thereof and over the conductor I68 and through the winding of relay I89 to ground. As a result of the energization of the relay I89 its armature I1I will be attracted thereto which results in a locking circuit being established from the battery I28 and through the winding of the relay I13 in a manner which has previously been described. Due to the energization of the relay I88 and the subsequent attraction of its armature 82 no circuit may be established at this time to cause the energization of the clutch release magnet 28, thereby precluding rotation of the shaft 22 and operation of the transmitter II for a cycle of operation. Thereafter as the brushes traverse the first five segments of the segmented distributor ring II a second code combination indicative of the character X will be transmitted over the line conductor 14 to the multiplex channel over circuits which are identical to those traced immediately above for the transmission of the first character X.

Inasmuch as the shaft 22 has been precluded from rotation for a cycle, or during the transmission of the second character X, no similar code combination will be transmitted over the start-stop circuit 29 inasmuch as the stationary position of shaft 22 precludes closing of the contact pair 44 for the energization of the clutch release magnet 3|.

After the brush traverses the first five segments to transmit the second X character designation, the other brush once again will traverse the segment I8 of the local ring 18 thereby bridging it with the solid ring 19 connected to battery 11 causing the establishment of an electrical circuit which may further be traced over the con-.- ductor 8! through the armature 82, through the upper contact with which it is now in engagement due to the energization of the relay I88, over the conductor I92 to the junction point I68, through the armature I81 and its upper contact in which it is now in engagement due to the energization of the relay I13, over the conductor I14 to junction point I16 and thence through the winding of the relay I11 to ground. The resultant energization of the relay I11 will cause its armature I2I to be attracted thereto thereby removing it from engagement with its associated contact II9 thus breaking the circuits from the battery I23 which had previously been traced as applying locking battery to the relays I42, I88, I13, and I89 thus resulting in all of these relays being de-energized. Upon de-energization of such relays the associated armaturcs will regain their position originally described whereby the apparatus is once again in condition to transmit another code combination over the multiplex channel.

Such other code combination will be available inasmuch as at the same time as the relay I11 was energized a second circuit was established which may be traced over the same circuit as just described up to junction point I16, and thence over conductors I18 and III and through the winding of clutch magnet 26 to ground, thereby causing the clutch magnet 26 to be energized. As a result of such energization the shaft 22 will once again be released for a cycle of rotation, thereby during its early part, causing the tape to be stepped to its next code combination position 15 a and the contact operators I! set in accordance with the marking or spacing conditions of the particular code combination to be sensed.

Itis to be remembered that at the outset of the description an idle channel condition was discussed at which time the contact operators I? were all in a clockwise or unselected position thereby allowing the swingers 62, through the elongated portion is, to be in their right-hand position in engagement with contacts 63. Contacts 63, as was also described, were connected to the relay bankl2 by means of conductors 68. In-tracing the circuit from the conductors 68 it is to be seen, with respect to the uppermost V swinger 62 and associated conductor for example, that the circuit continues through armature lit, over conductor 559, through armature I53 and thence over conductor I52. However, because of the fact that the relay I42 is not energized at this time the associated armature its will be in its upward position in engagement with its upper contact thereby precluding continuation of the just traced circuit from the conductor i5 2 to the conductor- ?2 and thence to the No. 1 segment of the segmented distributor ring it. However, a spacing or idle condition will still exist on the five segments indicating the present multiplex channel because of the fact that when the armatures Hi8 arein their upper positionengaging their upper contact, an electrical circuit is completed which may be traced from positive grounded spacing battery lot, over the common conductor t le, through the armatures Hi3, over the conductors 72 to the five segments of the segmented distributor ring ll comprising the present multiplex channel. Therefore, under this condition aspacing or idle channel condition will exist on the. multiplex channel, Thus, even though the swingers 62 are positioned an unselected or spacing condition the, circuit. is not tracedthe-reirom for the multiplex channel.

The above idle condition exists only aslong asv the instant apparatus is not in operation with either the manual switch d2. open or the swinger 96 biased away from engagement with itsassociated contact 9.6 thereby preventing energize,- tionor the; clutch release magnet 26 7 It is, however, to, be remembered that a condition: has been described above wherein upon the receipt oi a blank code, signal appearing in, a message text, the blank code combination is suppressed and instead; X, lettersi code. com binations are transmitted.- over the: multiplex channel. The difierence-between the twooperatr ing, conditions is due: to the fact that. at. such time as the instant apparatus is operating;- the manual; switch 92 will be closed as will. be the swinger 9.4, and, contact 96. thereby allowing energization: of, the clutch release magnet. 25 every time the brush traverses, the, segment. lid. Immediately uponl operation, ofthe shaft. 22. due to theenergization. ot the clutch release magnet 26 the cam 24 thereon will cause the contact-pair 119' tohe closed, resulting, in. the, relay [.42. being energized andzlockedup. over circuits, which have been previously traced At such; time, as :the relay- 142 becomes energized the armatures tw will be attracted thereto,,' thus removing them fromengagement With1their upper contacts and thereby removing; positive spacing battery, t5ilfromthe .armairures M8; and theconductors 12 IV isv also; toibe nememb cred-that. previously. in the description. mention was, made, thateif, a, code combinationywassensed other thansat-blanki or X combination; transmission at that'code. com:-

r '16 binationwouldoccur in accordance with the setting of the swingers 52. Atthat time mention was made that if the swinger 62 were in an unselected condition, a circuit was completed to the positive spacing battery 66, whereas if it were in a selected'or left-hand position a circuit was made with the negative marking battery 98. These circuits were traced through the swingers 62 to the conductors 68, Assuming now that a code combination exists which is neither blank nor X thereby not causing the reading relays III or I88 to be energized the circuit for the impulses of this code combination may be traced from the conductors 68' through the associated armatures !24' to I28, inclusive, which are in their upper position, over the conductors I59, through the armatures 553 to I51, inclusive, which are in their upper position, through: the conductors I52, through the armatures M8, which are in their lower position due to the energization of the relay I42, and over the conductors 12 to the first five segments of the segmented ring H. Thus, under this condition, as the brush bridges the solid ring 13 with the segmented ring 'H, cede impulses will be transmitted in accordance withthe setting of the swingers e2 over the line conductor- 74 to the multiplex channel.

It might be noted that when the code comrelay M12, through the armature He, will be broken inasmuch as the relay H! will beenergized thereby attracting. its armature 12 thereto removing it fromengagement with its contact I I 9 and breaking the locking batterycircuit. At the same time the clutch release magnet 2Q will be again energized resulting inthe shaft 22) being released for another cycle of: rotation with asubsequent closure of the contact pair F0 for again causing the energization of the relay I421 The apparatus will now be ready to. transmitthe next code. combination irrespective of what it may be when thebrushonce again-traverses the first five segments of thesegmented. ring 'I l Thereafter, depending upon the particular-code combination the apparatus will.v opera/taina manher; as, has: previously been described; depending on. whether a blanktl X,. or some: other code combination: is sensed and set in the associated contacts, a

Therefore, ithas beenseen: that in theeevent thata blank combination; issensed in amessag text. such. combination will be supressed and instead: an. Xf and letters combination will be transmitted! over. the multiplex channel. 1 Likewise, in the event tlziatv an combination is sensed and. set in, the associated contacts code combinations indicate oi X, XZ willlbe trans,- mitted; oven the. multiplex channel: a

Itshould be. noted. thatthe: relay, I142; invariably that: is, becomes energized. upomthe scttingcof. a character andthereafter'. becomes deiienergizedupon thetransmission 0t thatcharacter,

character has been transmitted iti-will, not be transmitted, a second-timein; the event-that the contact. operators. IJL remain. in, the samelposition due-tolnonew characterbeingreceivedandlset up, However, inzthe= event that asimilar character. is receiued. and set up therelay HZ wilL operate to allow transmission of the same; signall a second time, but; only because, a new signal. has been received; and. the. contact operators HI have been repositioned-,5 even thong-i to the same lwsitions operates This is true of the transmission of the last character by the pivoted transmitter, at which time the member 9'! will cause the swinger 94 to open contact pair 96, thus precluding operation of the clutch magnet 26, and thereby preventing energization of the relay I42 which is dependent on the release of the shaft 22 and the closure of the contact pair 10. The operation of the member 97 is described fully in the above-identified Gubisch patent. Thus, this character will only be transmitted once even though the multiplex distributor l3 continues to rotate.

It is to be understood that the present example has been illustrative only and therefore designations other than the express ones described may be used.

As may be seen by reference to Fig. l, the multiplex channel 14 will terminate at the receiving station in a receiving multiplex distributor 20! which has a solid and segmented ring similar to the rings 13 and 1!, respectively, of Fig. 2. The particular multiplex channel associated with the instant receiving station will have five of the segmented distributor segments connected to a multiplex to start-stop converter 202 which may be of the type disclosed in U. S. patent application Serial No. 495,857, filed by W. J. Zenner on July 23, 1943, now Patent No. 2,382,596, issued Aug. 14., 1945. The start-stop signals will then be received by a perforator transmitter 203 which is of the type disclosed in the above-mentioned Gubisch patent. The signals incoming to the perforator transmitter 203 will cause a tape to be perforated in accordance with their code combinations in a perforator section 204 which is shown schematically in Fig. 1 only. The prepared tape will then be fed to a tape transmitter 206 which forms part of the perforator transmitter 203 and which is disclosed more in detail in Fig. 3. The perforator transmitter 293 is similar to the one shown in Fig. 4 and referred to in the description of Fig. 2. A distributor 20'! also forms part of the perforator transmitter 203 and is also more fully disclosed in Fig. 3. A relay bank 208 is connected between the tape transmitter 206 and the distributor 2D! in a manner and for a purpose to be described hereinafter.

By referring to Fig. 3 it may be seen that the tape transmitter 206 of the perforator transmitter 203 is very similar to that disclosed and described with respect to Fig. 2. A shaft 2!! is provided which is under the control of a clutch release magnet 2!2 so that upon energization of the magnet the shaft will be released for operation. The clutch release magnet 2 2 is in an electrical circuit which may be traced from grounded battery 2I3, through the winding of the magnet 2 !2, through a manually operable switch 2!4, through a contact pair 2! 6 under the control of a member 2 I! which causes the contact pair to open at such time as the pivoted transmitter is in engagement with the punch block as described in the Gubisch patent, to ground.

The shaft 2! l is provided with three cams 2|8, 2i9, and 22! which control individual cam followers 222 to 224, inclusive, respectively. Each of the cam followers is normally biased in a clockwise direction under the urging of individual springs. The cam follower 222 controls an associated contact pair 226 which is normally open, for a purpose to be described hereinafter. The follower 223 controls an electrical contact pair 22'! which is normally closed whereas the follower 224 controls a contact pair 228 which is also normally closed.

The tape transmitter 206 is further provided with a plurality of slides 229 each of which controls a contact operator 23! similarly to that as described with respect to the transmitting station. The contact operators 23! each have an elongated section 232 which has a plurality of lugs 233 thereon each of which controls an associated electrical swinger. As has previously been described, the slides 229 are set in accordance with the code combination sensed in the tape and cause their associated contact operators 23! to be pivoted in a counterclockwise direction or not pivoted according to whether the particular impulse is of a marking or spacing variety.

The first lug 233 to the left of the contact operator 23! controls a, swinger 234 which does not make electrical contact in its right or unselected position but which upon being selected or moved toward the left engages a contact 233. The second lug 233 controls an electrical swinger 237 which may move between a left or right contact depending on whether the impulse is marking or spacing, respectively. The third lug 233 controls an electrical swinger 238 which may also move between a left or right contact similarly as with respect to swinger 231. The final or fourth lug 233 similarly controls a swinger 239 which is also movable between a left and right contact depending on a marking or spacing condition. While the above description has been made with respect to a single contact operator 23! and its associated swingers 234, 231, 238, and 239, it should be noted that each of the five contact operators 23! controls similar sets of swingers, each set of which represents an impulse in the five impulse start-stop Baudotcode.

Referring now to the distributor 201, also described as formin part of the perforator transmitter 233, it may be seen that it comprises a shaft 24! which is under the control of a clutch release magnet 242. The shaft 24! is provided with five cams 243 which have staggered low portions on the periphery thereof and operate to allow an associated follower 244 to pivot in a clockwise direction and close an associated contact pair 245 in a sequential manner with respect to the five cams. The shaft 24! is further provided with a sixth cam 24'! which controls a follower 248 which the start-stop code signals which have been received over the multiplex channel and converted to a local printer or over a. start-stop circuit 263 to remotely located equipment.

In the operation of the present apparatus the slides 229 will be positioned in accordance with the sensing of the tape after the shaft 2!! has started into rotation. The contact operators 23! will operate in accordance with the positioning of the slides 229 to position their associated swingers 234, 231, 238, and 239 also in accordance with the code combination sensed.

Just prior to the setting of the swingers but after the sensing pins have moved upwardly to sense the perforations in the tape, as is done in a well known manner, the shaft 2!! will reach such a position in its cycle of rotation whereat the cam 2 H will present its recess to the follower 222 thereby allowing the follower to pivot in a clockwise direction under the urging of its associated spring to close the contact pair 226. At this time an electrical circuit is established which may be traced from batteryv 256, 'over a common conductor 251, through the closed contact pair 226, over a conductor 258, and through the winding of the clutch release magnet 242 to ground. This will cause the magnet 242 to energize to release shaft 24l for operation.

Just prior to the release of the shaft 2 when the shaft is in a stationary position, the cam 241 thereon presents its recess to the follower 248 thereby allowing the follower to pivot in a clockwise direction to close the associated contact pair 249. Under this condition an electrical circuit is established from grounded battery 259, through the closed. contact pair 249, over a conductor 26l to junction point 262, and thence over the startstop circuit 263. Under this condition the startstop circuit will be in its idle condition with m'arking on the line as is well known to those versed in the art.

Upon the initiation of rotation of the shaft 24! the cam 241 will be rotated with respect to the follower 248 causing the follower to be pivoted in a counterclockwise direction which results in the contact pair 249 being opened; Under this conclutch release relay 242 is once again energized.

In the followin operational description let us assume that the slides 229 and the associated contact operators 23l have been positioned in accordance with a perforatedcombination in the tape in some code combination which differs from either a blank or X combination, as described with respect to the transmitter station. As a result of such positioning of the swingers 234 as may occur, one or more of the swingers may be positioned in its selected or left-hand position in engagement with contact 235. If such occurs, an electrical circuit may be traced from grounded battery 264, over a common conductor 266, through the contact 236, through the selected swinger 234, and over a conductor 261 to the relay bank 298.

By reference to the relay bank 268 it may be seen that the just described circuit is continued from the conductor 261, through an armature 268 which is normally in its upper position in engagement with an associated contact, over a conductor 269, through the contact pair 246 at such time as it is sequentiallyv closed, and over a common conductor 211 to the start-stop circuit 263.

This will result in a marking impulse on the startstop circuit 263 for each of the swingers 234 which has been selected and positioned in engagement with its associated contact 236.

In the event that a spacin condition exists with respect toswinger 234'it will remain in the position shown, not in engagement with any contact. Under this condition no electrical circuit is established and, therefore, when the contact pair 246 is closed in the sequential closingv thereof a zero'or spacing condition start-stop circuit 263. 7

Even though the swingers 231 to 239, inclusive, will also be positioned in accordance with the setting of the -slides'229, it is sufficient to state at this time thattheir positioning to a right or lefthand contact will have no effect under this condition inasmuch as they control reading relays responsive only to a letters and X condition. The letters combination would have no 'eliect on the reading relay under the control of the let-- ters swingers 231 even though it were to be set up by the slides 229 at this time, for a reason which will become apparent hereinafter. f 1

The tape transmitter apparatus 225 will operate continually upon the perforation of code com binations in the tape to cause these code combinations to be relayed to the start-stop circuit will exist on the V 263 similar to the manner just described.

It is to be remembered that with respect to the description of Fig. Zit was'pointed out that upon the occurrence of a blank combination, such combination was suppressed and instead X and letters combinations were transmitted over the multiplex channel 14. Also, upon the occurrence of an X.condition it was converted to X,

code combinations prior to transmission over the multiplex channel 14.

Let it now, be assumed that a condition exists at the receiving station whereat the tape which is prepared by the perforator 264 reaches a position in the tape transmitter 266 where the swingers 226 will be positioned in accordance with X, flett-ers combinations designating a blank code signal transmitted. Under this assumed condition the slides 229 and associated contact operators 23! would be positioned in accordance with an X code combination which is represented by a marking impulse, a spacing impulse,

ers 238 and 239 are positioned in accordance with the description just given, an electrical circuit is established which may be traced from battery 256, over the common conductor 251, through the contact pair 221 which is normally closed, over a conductor 212, through the No. 1 swinger 238 which is positioned to the left, over a conductor 213 to the No. 2 swinger 238 which is positioned as shown or to the right, over a conductor 214 to the third swinger which is positioned toward the left, over a conductor 216' to the fourth swinger also positioned toward the left, through a con-' ductor 211 to the fifth swinger also positioned toward the left, over a conductor 218 to junction point 219, over a conductor 28 l through an armature 282 which is normally in its unattracted position in engagement with an associated upper contact, over a conductor 283 to the junction point 262 and to the start-stop circuit 263. The result of such circuit, which is established just prior to the opening of the contact pair 249 to establish a start condition on the start-stop circuit 263 is to operate as a shunt andtherebypreclude a start condition from existing on the startstop circuit 263. The result of such occurrence is that the start-stop circuit 263 remains as though there were an idle conditionwith marking on the line and the local printer or; remotely located equipment associated with the line will not respond in any manner to this X combination in the tape transmitter 206.

A second electrical circuit is established over the circuit previously traced to the junction point 219 and thence through an armature 284 which is normally in its unattracted position in engagement with its lower contact, over a conductor 285 to junction point 299, and through the winding of a relay 281 to ground. The relay 281 energizes and causes its armatures 288, 289, and 291 to be attracted thereto conditioning electrical circuits with their associated contacts but not establishing any at this time for reasons which will hereinafter appear. There is no locking circuit for the relay 281 inasmuch as it will remain energized over the circuit just traced for the period of time that the contact pair 221 is closed.

As was previously mentioned, the swingers 239 were also positioned similarly as were the swingers 238. Upon such occurrence a second electrical circuit may be conditioned from battery 256, through normally closed contact pair 228, over a conductor 292, through the swingers 239 and conductors connected thereto in a manner as was described with respect to the swingers 238, over a conductor 293 to junction point 294, thence over a conductor 296, through the winding of a relay 291, over a conductor 298, and through the armature 289 to junction point 299.

The relay 291 will not be energized, however, because as previously described positive battery was also applied over conductor 286 to junction point 299. Therefore, inasmuch as positive battery is applied to both sides of the winding of relay 291 no difierential exists and, therefore, this relay cannot be energized. Thus, it has been seen that while the X of the X, letters combination has been received it will not be retransmitted over the start-stop circuit 263. In other words, the instant apparatus under description acts to determine whether X, letters or X, X combination is being received for retransmission and controls the initial X to condition the apparatus only, no retransmission occurring thereof.

Near the end of the cycle of operation of the shaft 2 but while the contact pair 221 is still closed causing the relay 281 to remain energized, the cam 25! on the shaft 24! presents its recess to its follower 252 thereby allowing the follower to move in a clockwise direction under the urging of its associated spring thereby closing the contact pair 253. When this occurs a further electrical circuit is conditioned which may be traced from grounded battery 30!, through the now closed contact pair 253, over a conductor 302, through an armature 303 which is in an unattracted position in engagement with its associated contact, over a conductor 304 to junction point 294, thence over conductor 296, through the winding of relay 291, over conductor 298, through the armature 289 to junction point 299. The relay 291 will not become energized at this time because as pre viously described positive battery was also applied over the conductor 286 to junction point 299 and therefore as positive battery is being applied to both sides of the winding of the relay 291 the relay will not energize. However, shortly after the contact pair 253 has been closed and while it is still in such condition the cam 219 will present its high portion to its associated follower 223 thereby pivoting the follower in a counterclockwise direction and allowing the contact pair 221 to open. As a result of the opening of this contact pair a circuit no longer can be traced through the swingers 238 and eventually over the conductor 283 to the start-stop circuit 263 with the result that the marking on the line shunt circuit will no longer exist. However, such occurrence is so timed that the cam 241 will cause the contact pair 249 to be closed just prior thereto thereby supplying battery 259 to the start-stop circuit 263* and thus maintaining a marking condition on that circuit.

A second result of the contact pair 221 being opened is that positive battery is no longer applied over conductor 286 to the junction point 299 in opposition to the battery applied through the winding of the relay 291. Thus, at this time the relay 291 becomes energized due to the previous closing of the contact pair 253 over a circuit originating with battery 30] and which may be traced further from the junction point 299 and through the winding of relay 281 to ground. The relay 291 now becomes energized, attracting its armatures 282 and 284 thereto with the subsequent breaking of previously established electrical circuits.

Having assumed previously that the incoming signal was X, letters combinations, the letters combination will now be set by the slides 229 in the various swingers associated with the contact operators 23L Inasmuch as a letters combination consists of all-marking code impulses all of the swingers will be positioned in their selected or toward the left position in engagement with their left-hand contacts. It is to be remembered that previously a circuit was described wherein upon the selection of one of the swingers 236 a circuit was established from battery 264, through the conductor 266, through the contact 236 and the swinger 234 and thence through the relay bank 208 to the distributor 201. However, such a combination is not desired at this time inasmuch as the original code combination was blank and not a letters combination. Therefore, at such time as the swingers 231 are moved in engagement with their left-hand contacts an electrical circuit is conditioned through the five swingers and their connecting conductors and over a conductor 306. Assume now that the shaft 2| I has rotated sufiiciently for its cam 2I9 to once again cause the contact pair 221 to be closed. An electrical circuit may be traced from battery 256, over the common conductor 251, through the contact pair 221, over the conductor 212, through the swingers 231 and their connecting conductors, over the conductor 306, through the armature 288 which is in its attracted position in engagement with its contact, over a conductor 301, and through the winding Of a relay 308 to ground. The energization of the relay 308 will cause its armature 309 to be attracted thereto thus providing a locking circuit for the relay through the armature 309 and a conductor 3 back to the conductor 306, thus shunting the armature 309. Therefore, after the armature 288 no longer remains attracted the relay 308 will still remain energized. The energization of the relay 308 also causes its five armatures 268 to be attracted thereto removing them from engagement with their associated contacts. Thus, despite the fact that the swingers 234 have all been positioned in their selected position toward the left no circuit may be established from the battery 264, over conductors 261 to the contact pairs 246 for sequential closure because of the opening in the circuit at the armatures 268. Therefore, as the cams 243 sequentially close the associated con- 23 tacts 246,through the action of the followers 12, a spacing or zero condition will exist on the startstop circuit 263 which will cause the apparatus associated therewith, either local r remote, to

be operated in accordance with a blank code combination. Thus, it has been seen that upon the receipt of an X, letters combination the apparatus at the receiving station will operate to convert these code combinations back to a blank code combination which they originally designated.

Even though the contacts 221 and 22B are held closed during the above-mentioned interval of the letters combination, they will have no eifect with respect to the apparatus inasmuch as the second swingers 238 and 239 will both be positioned in their selected or left-hand position thereby precluding the tracing of an electrical circuit to either of the conductors 218 or 293. I 1

After the contact pair 253 opens, batterywill no longer be applied to to the junction point 23 and, therefore, the relays 291 and 281 will become de-energized. However, inasmuch as this does not occur until after the relay 3&8 has become energized and locking battery is applied thereto, shunting armature 288, no adverse effect is had on the apparatus, particularly the relay 3H8.

The apparatus thereafter operates with the slides 229 setting anew character in accordance with the combinationsensed in the tape. At such time the contact pair 221 will be open and no circuit may be traced through the swingers 231 and. their conductors to apply locking battery to the relay 308, and therefore this relay will become to return to their normal condition in'engagement with their associated contacts. The apparatus will now be ready to repeat a cycle of operation. 1

Now assume that instead of X, letters combinations being received by the instant apparatus X, X code combinations are received which are indicative of the character X alone. .The instant apparatus will operate with respect to the first X as has been described previously to cause the energization of the relay 281 and the shunt circuit for the start-stop circuit 263 during the receipt of the first X. Atsuch time as the second X is set in the swingers by means of the contact operators 23l the shunt circuit for the start-stop circuit 263 will no longer exist because of the energization of the relay 291 and the subsequent attracting of its armature 282, as previously described. Likewise, the circuit for the energization of the relay 281, through the conductor 286 and junction point 293 will no longer exist because of the attraction of the armature 233 to its upper contact instead of its lower contact. However, at this time the relay 281 will remain energized'through a circuitincluding the swingers 239, the conductor 293 to the junction point 294, over the conductor 296, through the Winding of the relay 291, over the conductor 298, through the armature 289, and thence through the winding of the relay 281 to ground. This circuit is established during the closure of the contact pair 228, prior to the time that the contact pair 253 is opened, therefore, insuring that the relay 281 will remain energized continually from the receipt of the initial X code combination.

An electrical circuit is established upon-the setting of the swingers 238 in an X code com bination'which maybe traoedfrom the battery 256, through the common conductor 251, through attracting its armature 314 thereto and thus supplying locking battery for the relay 3l3 through its lower winding, over a conductor 1H6, through the armature 29| which is in its attracted position in engagement with its contact, and through the contact to grounded battery 3".

As a result of the energization of the relay 3I3- and its remaining in a locked up condition the armature 303 will be attracted thereto removing it from engagement with its associated contact and thereby precluding the electrical circuit through the contact pair 253 to the battery 33! in the event that such circuit were conditioned by the closure of the contact pair 253 through the action of the cam 25L Inasmuch as an "2? code combination has been set up in the swingers 231, no electrical circuit may be traced through these swingers and their connecting conductors to cause the energization of the relay 398 because the second swinger 231 will be held in its unselected or-right-hand position'because of the second impulse of an X code combination being spacing,thereby precluding the completion of a circuit through the arma tures and connecting conductors. Inasmuch as the relay 308 does not become energized the armatures 268 will remain in engagement with their 7 associated contacts, thus completing circuits from the battery 264, through the contacts 236;. and selected swingers 234. If the swinger 232 is in its unselected condition as the second one will be, no circuit will be establishedthrough the asso-, ciated contact 236. Therefore, as the shaft 2M is released for rotationunder the, action of the clutch release magnet 242 and progresses suflii ciently to cause the sequential closure of the contacts 246, code impulses indicative of an fX combination; that is, marking, spacing, marking, marking, marking, will be transmitted over the start-stop circuit 263. Thus, a code signal indicative of the character X will be transmitted over the start-stop circuit 263, the initial ,X being operation of scribed as holding the relay 281. energized during the interval of changing of the code combinations in the swingers under the control of the slides 229 and the contact operators 23L Inasmuch as the relay 3l3 is energized'and the armature 383 is attracted thereto this circuit cannot be established and, therefore, .at such time as the-contact pair .228 is opened the relays 281 and 291-will become de-energized. "Atthis time the armature 25 of the relay 281 will return to its unattracted position, breaking the circuit from battery 3|? to'the locking winding of the relay 3l3. The relay 3l3 will thus become tie-energized allowing its armature 303 to assume its unattracted position in engagement with its contact in readiness for the possible establishment of a circuit from battery 30! through the contact pair 253 the'next 25 time this contact pair is closed (next cycle of rotation of shaft 241).

Inasmuch as the relays 281, 291, and SH have all become de-energized the apparatus is now in readiness to resume its operation upon the next incoming code signal. In the event that such signal were to be another combination the first character of which was X, one of the two conditions previously described would occur and the apparatus would operate in a manner similar to that already described.

While the instant invention has been described with respect to particular apparatus, it is obvious that it could be incorporated in apparatus of other types where a similar need is present. Likewise, while specific code combinations have been utilized designating a, blank code combination it is obvious that any desired code combination may be utilized. Thus, the specific disclosure is illustrative only and the invention may be embodied in other types of apparatus.

What is claimed is:

1. In a telegraph transmitter, means to initiate code combinations in accordance with perforations in a tape, means operating upon the initiation by said initiating means of a predetermined code combination to convert it to tWo code combinations neither of which are the same, and means operating upon the initiation by said initiating means of a code combination in the tape similar to the first of said converted code combinations to convert said code combination in the tape to two code combinations both of which are the same.

2. In combination with a telegraph transmitter, a multiplex channel, means to transmit all-spacing impulses over said multiplex channel when said transmitter is in an idle condition, means to initiate code combinations in accordance with the perforations in a tape when said transmitter is operating, and means operating when an allspacing code combination is initiated during the operation of said initiating means to convert it to a difierent code combination for transmission over said multiplex channel.

3. In a telegraph receiver, means to receive code signals, a distributor under the control of said received code signals, means to shunt said disstributor upon the receipt of a predetermined code signal, means to distinguish the code signal following said predetermined code signal, and means to convert said following code signal to a difierent code signal prior to the operation of said distributor if it designates a particular character.

4. In a telegraph receiver, means to receive code signals, a plurality of sets of contacts set in accordance with the received code signals, means under the control of one of said sets of contacts to cause said telegraph receiver to be nonresponsive to a predetermined code signal, and means under the control of another of said sets of contacts to cause another predetermined code signal to be converted to a still different code signal.

5. In a. telegraph system including a transmitter and a receiver, code signal initiating means at said transmitter, means operating upon the initiation of a predetermined code signal to convert it to two code signals neither of which are the same, means operating upon the initiation by said code signal initiating means of a code signal similar to the first of said converted code signals to convert it to two code signals both of which are the same and are similar to the initiated code signal, means to transmit said code signals to said receiver, means at said receiver responsive to the received 26 code signals, means to suppress the first of the code signals of said converted two code signals, means conjointly responsive to said two difierent code signals to cause the second code signal to be converted, and means conjointly responsive to said two same code signals to allow the second code signal to be unaltered.

6. In combination with a transmitter having a pivoted tape sensing device for sensing the last character perforated, electrical contacts set in accordance with the sensing, and a member operated upon the sensing of the last character, a multiplex distributor, electrical contacts associated with said distributor, means operating after the sensing of a character for connecting said second-named electrical contacts with said distributor and said first-named electrical contacts, and means under the control of said member to preclude operation of said first-named means, whereby said second-named electrical contacts will not connect said distributor with said firstnamed electrical contacts after the transmission of the last character.

7. In combination with a transmitter having a pivoted tape sensing device for sensing the last character perforated, electrical contacts set in accordance with the sensing, and a member operated upon the sensing of the last character, a multiplex distributor, electrical contacts associated with said distributor, means operating after the sensing of a character for connecting said second-named electrical contacts with said distributor and said first-named electrical contacts, means associated with said distributor for releasing said first-named means from operation after the character has been transmitted by said distributor, and means under the control of said member to preclude operation of said first-named means, whereby said second-named electrical contacts will not connect said distributor with said first-named electrical contacts after the transmission of the last character.

8. In combination with a transmitter having a pivoted tape sensing device for sensing the last character perforated, electrical contacts set in accordance with the sensing, and a member operated upon the sensing of the last character, a multiplex distributor, electrical contacts associated with said distributor, a relay operating after the sensing of a character for connecting said second-named electrical contacts with said distributor and said first-named electrical contacts, and means under the control of said member to preclude operation of said relay, whereby said second-named electrical contacts will not connect said distributor with said first-named electrical contacts after the transmission of the last character.

9. In combination with a transmitter having a pivoted tape sensing device for sensing the last character perforated, electrical contacts set in accordance with the sensing, and a member operated upon the sensing of the last, character, a multiplex distributor, electrical contacts associated with said distributor, means operating after the sensing of a character for connecting said second-named electrical contacts with said distributor and said first-named electrical contacts, means under the control of said member to preclude operation of said first-named means, whereby said second-named electrical contacts will not connect said distributor with said firstnamed electrical contacts after the transmission of the last character, and means to supply a blank signal combination to said second-named electrical contacts and said distributor during the operation of said second named means. a

10. In combination with a transmitter having a pivoted tape sensing device for sensing the last character perforated, meansset in accordance with the sensing, and a member operatedupon the sensing of the last character, a multiplex distributor, means operating after the sensing of a character to operatively connect said means set in accordance with the sensing and said distributor toltransmit signals, means under the control of said member to preclude operation of said lastnarned means, and means coacting with said means under the control. of said member when it is operated to supply a blank signal combination to said distributor.

11. In combination with a transmitter having a pivoted tape sensing device for sensing the last character perforated, and a member operated upon the sensing of the last character, a multiplex distributor, 'means for supplying signals'to said distributor for transmission from said sensing device after it senses a character, means under the control of said member operated upon the sensing of the last character to precludesaid last-named means from supplying the last character sensed by said sensing device to said distributor more than once, and means under the control of said precluding means for supplying a blank signal combination to said distributor during the remainder of time that said member is operated.

12. In a telegraph transmitter, means to initiate code -combinations" in accordance with perforations in a tape, means'operating upon the initiation of a. predetermined'code combination by said initiatingmeans to convert said code com bination in the tape to a plural code combina- REFERENCES or'rEn I The following references are of record in the file of this'patent:

UNITED STATES PATENTS Number Name Date 1,356,546 Morehouse Oct.26, 1920 1,966,382 Haglund July 10, 1934 2,109,989 Dirkes Mar. 1, 1938 2,152,772 Potts Apr. 4, 1939 2,379,865

Connery July 10, 1945 

